Peter Neubäcker, a former German guitar maker turned programmer, has done what many in the computer-music business believed impossible.

A new piece of software called Direct Note Access, first publicly demonstrated by Neubäcker and his company Celemony Software last month, will for the first time allow computers to analyze the digitized sounds of guitar or piano chords, or even multi-instrument recordings, and then extract and modify individual notes.

Computers have revolutionized the recording process, giving sound engineers wide latitude to manipulate notes recorded singly--to change their pitch, their tempo, or where they fall. But teasing apart notes recorded simultaneously, as in a six-string guitar chord, has never before been practical.

"In terms of sound processing, this is kind of the holy grail," says Michael Bierylo, a guitarist and professor of computer music at Boston's Berklee College of Music. "It's something everyone more or less thought we couldn't do."

Aren't they the makers of Melodyne? I thought in that you could manipulate the notes provided you had expanded things out to see them within the waveform? My buddy has it, it's an interesting piece of software. I am not sure how often he uses it though.